Django on Heroku: installing NodeJS and Less for static assets compilation

Heroku provides a bunch of different buildpacks that target many popular platforms like Python, Ruby, NodeJS and Java web apps and backends. While this is great and allows you to deploy virtually anything with a simple git command, the out-of-the-box solutions offer a limited set of utilities that are available during the Slug compilation phase. In particular, no NodeJS, NPM or LESS Compiler is available in the heroku-buildpack-python. This means that there is no straightforward way of compiling .less stylesheets during the app deployment.

Fortunately, the Python buildpack provides hooks for running pre-compile and post-compile scripts. This can be used for customizing the compilation step and running additional commands without the necessity of maintaining a separate fork of Heroku's buildpack. The only thing you need to do is to create a proper bin/post_compilebash script in the root directory of your application.

Head on to the Django and Heroku Cookbook repository for a set of post-compile scripts. The bin directory contains a set of scripts that can be used to install NodeJS/Less and invoke the manage.py compress command in your Django application:

• bin/post_compile
• bin/install_nodejs
• bin/install_less
• bin/run_compress

Just copy them over to your app reposiory and have your Less stylesheets compiled with an assets compressor like Django Compressor.